Pregabalin for Neuropathic Pain in Post-radiotherapy Head and Neck Cancer Patients: A Retrospective Study and Review of the Literature.

INTRODUCTION

Head and neck cancer (HNC) patients may experience neuropathic pain (NP) due to radiotherapy (RT), which may become chronic. Pregabalin, an anticonvulsant, alters the transmission of painful stimuli at the synaptic level, modifying their perception. Pregabalin is used in NP treatment, but limited data exist on RT-treated HNC patients. This retrospective study aimed to present a case series of HNC patients with chronic NP after RT managed with pregabalin.

METHODS

HNC patients' records from the Department of Oral Medicine and Pathology and Hospital Dentistry, School of Dentistry, National and Kapodistrian University of Athens (NKUA), were searched. Outcome measures were obtained using the Douleur Neuropathique 4 (DN4) scale for NP and the numeric rating scale (NRS) for pain. The use of additional analgesic medication was also recorded.

RESULTS

Five HNC (four oral and one nasopharyngeal cancer) patients (mean age 58.5 years) who had received RT (mean total dose 64.7 gray (Gy)) and developed chronic (i.e., present for at least three months after RT) NP, characterized by a positive DN4 score ≥4, were identified. The initial assessment was five months to six years after RT (mean DN4=4.6±0.89 and mean NRS=6±3.08). "Burning," "pins and needles," and "numbness" were the NP descriptors mostly used. Pregabalin was titrated up to 150-300 mg per day; paracetamol and/or tramadol were also administered (daily doses 3000 mg and 100-150 mg, respectively). A substantial pain relief (≥50%) according to the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) (mean DN4=1.6±1.67 and NRS=1.6±1.67) was reported after two to three months of treatment, when tapering was initiated. Two patients (2/5) had complete remission of symptoms (DN4=0, NRS=0). No serious adverse effects were reported; one patient reported excess salivation.

CONCLUSIONS

Pregabalin may be a promising option for managing RT-related chronic NP in HNC patients. Further studies, including randomized controlled trials on RT-treated HNC patients, should be conducted.